快樂小藥師 Im pharmacist nichts glücklich

Paraquat（除草劑，不是有機磷農藥） inoxication，今天剛好有一位這樣的病患住進來，所以就在這邊寫一下說明給大家知道。

1.A herbicide (weed killer), inactivated by contact with soil

2.Lethal dose for man: can be as small as 4 mg/kg B.W.（about 1/2 tsp of 20% solution）

3.Commercial products in Taiwan: 20-25% Paraquat sol'n

4.Mechanism of toxicity: Seems to be the fllowing:

　－Paraquat + e- (from NADPH)→Reduced

　－Paraquat Radical

　－Reduced Paraquat Redical + Oxygen→Molecule

　－*O2 produce severe tissue damage directly, & Molecule Paraquat reused.

　－2O2 + 2H + superoxide dismutase H2O2 + O2

　－*H2O2 aain cause tissue damage

5.History, S/S: large dose lead to rapid induction of pulmonary edema & hemorrhage; in smaller dose cases, usually remain well for several days the resp. distress, oligouria, jaundice; local　irritation to eyes, skin, nose, throat occur rapidly.

6.Treatment

　1)Gastric lavage thoroughly and test urine (Ref 1)

　2)Activated charcola 10 gm, Castor oil 30 ml po.

　3)Give 30% Fuller's Earth orally (or 7% Bentonite the same volume)

　　a) 1 liter stat

　　b) 200-500 ml Q 2 hrs for 1 day

　　c) 200-500 ml Q 4 hrs for the 2nd day

　4)Give purgatives

　　Mg sulfate 2gm Q 2 hrs for 1 day

　　　　　　　2gm Q 3 hrs for the 2nd day

　5)Balance I/O and electrolytes

　6)Hemoperfusion (preferable) & Hemodialysis: most efficient

　　(valuable in anuria case)

　　Forced diuresis: less efficient

　　Peritneal dialysis: nearly no effect

　7)Delay the use of O2: since increase oxygen tension will increase the

　　production of Superoxide ion. When resp. distress present, give O2 care

　　fully only to keep PO2 above 40 mmHg.

　8)IPPB p.r.n to combat atelectasis or pulm onary edema

　9)May give corticosteriod or immunosuppressive agents (?)

　10)May give large dose Ascorbic acid (antioxidant, strong reducing agent)

　11)Nose, throat skin: irrigate out Paraquat and symptomatic treatment.

　12)Eye: irrigation with water for 10-15 min. give antibiotic oint. To prevent infection, later, when

regrowth of corneal & conj. epith. is completed,give steroid oint. to aid resolution of granulation.

Ref.1.Qualitative urine exam. for Paraquat Fresh preparation of Reagent Hydrosulfite)

　　　2 ml Reagent + 10 ml urine------Green or blue→(+)

　　　Sensitivity: 1.0 mg/L (1 ug/ml) > lethal dose

　　2.Poor prognostic signs

　　　1)Large dose ingestion

　　　2)Delayed treatment

　　　3)Low urinary excretion rate

　　　4)Early pul. manifestation

　　3.Emergent tratment if far from the hospital: except gap vomiting,fed the p's by swalloowing

     cooled, boiled earth from the yard, because paraquate is less toxicated when touched by

     earth.

上面太複雜，寫簡單一點：

在急診時：

1.Decontamination from skin

2.Set IV line with N/S

3.CBC & Dc, Bio, Urine paraquat, Blood araquat

4.ABC

5.On N-G tube: Gastric irrigation Activated charcoal (1 gm/kg)

6.CXR

7.EKG

進了加護病房：

1.Ringer's solution 1000 ml IVD Qd

　D5W 1000 ml IVD Qd

　N/S 1000 ml IVD Qd

2.KCL 40 meq IVD Qd

3.Tagamet 1 Amp V drip q 8 h

4.C- meta 1 Amp V drip q 8 h

5.NPO, N-G keep open

6.On CVP, check q2h

7.Paraquat urine > + then Hemoperfusion, On DHP1 protocol

　On double lumen: femoral vein

　Heparin 10,000 unit IV st

　Heparin 1,000 unit/hr IV infusion keep APTT 1.5-2 fole

8.ABG qd & Prn

9.CXR qd

10.Paraquat urine qd until undetectable

11.APTT q2h check

12.CBC & Dc qod

13.Na, K, GOT/GPT BUN/Cr qd

另外，有藥師朋友也寫過這樣的文章，提供給大家參考：

http://jerryljw.blogspot.com/2007/04/paraquat-intoxication.html